Reversible spring retention assembly for a valve

ABSTRACT

A valve assembly with a spring retention assembly including an elongated cylinder portion having an open threaded end and a closed end and an elongated piston portion having a free end and a threaded tab end configured to thread through the open threaded end and, thereby, be slideably captured in the cylinder portion. A spring couples to the body portion and the piston portion to provide a force to urge the body portion and the piston away from one another, wherein the closed end and the free end are similarly shaped so that the spring retention assembly can be reversibly mounted to a valve member that can also be reversibly mounted.

CROSS-REFERENCE

This application is a division of and claims the benefit of U.S. patentapplication Ser. No. 17/402,737 entitled BACKFLOW PREVENTION ASSEMBLYWITH TELESCOPING BIAS ASSEMBLY AND REVERSIBLE VALVE MEMBER, filed onAug. 16, 2021, which claims priority to U.S. Provisional PatentApplication No. 63/066,411 entitled BACKFLOW PREVENTION ASSEMBLY WITHTELESCOPING BIAS ASSEMBLY AND REVERSIBLE VALVE MEMBER, filed Aug. 17,2020 under 55 U.S.C. § 119(e), each of which is incorporated herein byreference in its entirety and for all purposes.

FIELD OF THE DISCLOSURE

The subject disclosure relates to backflow prevention valves andassemblies, and more particularly to backflow prevention valves andassemblies having a reversible telescoping bias spring retentionassembly coupled to a reversible valve member.

BACKGROUND

In many water systems, backflow prevention (BFP) assemblies allow fluidand even solids to flow only in a desired, i.e., a forward, direction.As backsiphonage or backflow can present contamination and healthproblems, the backflow prevention valves and assemblies prevent flow inan undesired direction, i.e., a backward or reverse direction. BFPassemblies are installed in buildings, such as residential homes, andcommercial buildings and factories, to protect public water supplies bypreventing the reverse flow of water from the buildings back into thepublic water supply.

A typical BFP assembly includes an inlet shutoff valve and an outletshutoff valve with a backflow prevention valve assembly extendingbetween the inlet and outlet shutoff valves. Many differentconfigurations of BFP assemblies are commercially available, each beingdifferently configured.

Owing to the fact that BFP assemblies are important for water safety,BFP units are tested annually, often per government regulations, toassure proper operating condition. Specifically, fluid pressuremeasurements are taken at specified locations in the BFP unit. If it isdetermined that a check valve needs to be repaired or replaced, theinlet and outlet shutoff valves have to be closed, the check valve fixedand tested, the shutoff valves opened and the apparatus confirmed to beoperating per any required ordinances and/or standards. The process istime-consuming and the steps have to be performed in the correctsequence and manner in order to not contaminate the public water supply,inadvertently flood an area, and return the BFP assembly to workingorder.

SUMMARY

From time to time, various components of a BFP assembly may needreplacement, which is not only difficult and time consuming but resultsin downtime for the fluid network. Components for the BFP assembly thatare easier to manufacture, assemble and install as well as more robustwould reduce: the difficulty of fabrication and repair; repair time;assembly error from improper fabrication or otherwise; and thedifficulty of installation. Preferably, a telescoping spring retainerassembly provides some or all of these benefits along with reducing therequired components. When the telescoping spring retainer assembly iscoupled to a reversible valve member, these benefits are furtherenhanced.

The subject technology is directed to a valve assembly including aspring retention assembly coupled to a valve member. The springretention assembly has an elongated cylinder portion having an openthreaded end and a closed end. An elongated piston portion has a freeend and a threaded tab end configured to thread through the openthreaded end and, thereby, be slideably captured in the cylinderportion. A spring couples to the body portion and the piston portion toprovide a force to urge the body portion and the piston away from oneanother, wherein the closed end and the free end are similarly shaped sothat the spring retention assembly can be reversibly mounted. A valvemember includes a central disc having a first side and a second side,each side forming a sealing region and having a retention cup, whereinboth retention cups can capture the closed end or the free end so thatthe valve member is reversible. A hinge portion extends radially fromthe central disc.

In one embodiment, the subject disclosure is directed to a springretention assembly for a valve assembly, comprising an elongatedcylinder portion having an open threaded end and a closed end. Anelongated piston portion has a free end and a threaded tab endconfigured to thread through the open threaded end and, thereby, beslideably captured in the cylinder portion. A helical spring couples tothe body portion and the piston portion to provide a three to urge thebody portion and the piston away from one another, wherein the closedend and the free end are similarly shaped so that the spring retentionassembly can be reversibly mounted.

In another embodiment, the subject disclosure is directed to a springretention assembly for a valve assembly having a cylinder portion withan open threaded end. A piston portion has a threaded tab end configuredto thread through the open threaded end and, thereby, be captured in thecylinder portion for sliding motion. A spring couples to the bodyportion and the piston portion to provide a force to urge the bodyportion and the piston away from one another. Preferably, the cylinderportion has a closed end. with a retention collar, the piston portionhas a retention collar, and the spring extends between the retentioncollars. The spring may be under a predetermined amount of compressionless than an amount of force of a normal forward flow of fluid in thebackflow prevention system. The inner diameter of the cylinder portionand an outer diameter of the threaded tab end can be approximately equalso that lateral movement of the piston portion is reduced.

In still another embodiment, the subject disclosure is directed to aspring retention assembly for a valve assembly that includes atelescoping central portion with a first free end and a second free end,wherein the ends are similarly shaped so that the spring retentionassembly can be reversibly mounted. Preferably, the ends are bulbous tofit in a hollow formed in the housing of the valve assembly or aretention cup of the valve element. Another embodiment includes a firstretention collar on the first free end, a second retention collar on thesecond free end, and a spring extending between the retention collars sothat the ends are configured to mount to either retention collar forsimplification of the parts required.

The subject technology is also directed to a valve member for a valveassembly including a central disc having a first side and a second side,each side forming a sealing region and having a retention cup, whereinthe sealing regions and the retention cups are similarly shaped so thatthe valve member is reversible. A hinge portion extends radially fromthe central disc. The sealing regions may be ring-shaped elastomericinserts. Preferably, the retention cups are centrally located on therespective side with a plurality of deflectable fingers for receiving aspherical end of a spring retention assembly. By being the same shapeand size, the deflectable fingers facilitate either side interactingwith the spring retention assembly. By the first and second sides beingsymmetrical about an axis, reversibility of the valve member is alsofacilitated. In one embodiment, the hinge portion includes a pair ofopposing arms extending radially from the central disc and having distalprotruding tabs.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects of the present disclosure are discussed herein withreference to the accompanying Figures. It will be appreciated that forsimplicity and clarity of illustration, elements shown in the drawingshave not necessarily been drawn accurately or to scale. For example, thedimensions of some of the elements can be exaggerated relative to otherelements for clarity or several physical components can be included inone functional block or element. Further, where considered appropriate,reference numerals can be repeated among the drawings to indicatecorresponding or analogous elements. For purposes of clarity, however,not every component can be labeled in every drawing. The Figures areprovided for the purposes of illustration and explanation and are notintended as a definition of the limits of the disclosure.

FIG. 1 is a cross-sectional view of a backflow prevention BFP assemblywith only the second check valve assembly open in accordance with thepresent disclosure.

FIG. 2 is a cross-sectional view of the BFP assembly of FIG. 1 with bothcheck valve assemblies closed in accordance with the present disclosure.

FIG. 3 is perspective view of a telescoping spring retainer assembly inan extended position for a check valve assembly for a BFP assembly inaccordance with the present disclosure.

FIG. 4 is a plan view of the telescoping spring retainer assembly ofFIG. 3 .

FIG. 5 is a cross-sectional view of the telescoping spring retainerassembly taken along line 5-5 of FIG. 4 .

FIG. 6 is a partial detailed cross-section view of the telescopingspring retainer assembly shown in circle 6 of FIG. 5 .

FIG. 7 is a perspective view of the telescoping spring retainer assemblyof FIG. 3 in a compressed position.

FIG. 8 is a plan view of the telescoping spring retainer assembly ofFIG. 7 .

FIG. 9 is a cross-sectional view of the telescoping spring retainerassembly taken along line 9-9 of FIG. 8 .

FIG. 10 is a partial detailed cross-section view of the telescopingspring retainer assembly shown in circle 10 of FIG. 9 .

FIG. 11A is an isolated side view of a frame for use in a check valveassembly in accordance with the subject disclosure.

FIG. 11B is an isolated perspective view of a frame for use in a checkvalve assembly in accordance with the subject disclosure.

FIG. 12 is a partial cross-sectional view of a reversible valve membercoupled to a frame in a check valve assembly in accordance with thesubject disclosure.

FIG. 13A is an isolated perspective view of another reversible valveelement for use in a check valve assembly in accordance with the subjectdisclosure.

FIG. 13B is a cross-sectional view of the reversible valve member ofFIG. 13A.

FIG. 14 is an isolated perspective view of a telescoping springretention assembly coupled to a reversible valve member for use in acheck valve assembly in accordance with the subject disclosure.

FIG. 15 is perspective exploded view of another telescoping springretainer assembly for a check valve assembly for a BFP assembly inaccordance with the present disclosure.

FIG. 16 is a side view of the telescoping spring retainer assembly ofFIG. 15 with the spring removed.

FIG. 17 is another side view of the telescoping spring retainer assemblyof FIG. 15 .

FIG. 18 is a partial perspective view of the cylinder portion of thetelescoping spring retainer assembly of FIG. 15 .

DETAILED DESCRIPTION

The subject technology overcomes many of the prior art problemsassociated with backflow prevention assemblies. The advantages, andother features of the technology disclosed herein, will become morereadily apparent to those having ordinary skill in the art from thefollowing detailed description of certain exemplary embodiments taken incombination with the drawings and wherein like reference numeralsidentify similar structural elements. It should be noted thatdirectional indications such as vertical, horizontal, upward, downward,right, left and the like, are used with respect to the figures and notmeant in a limiting manner.

Referring now to FIGS. 1 and 2 , there is shown a backflow prevention(BFP) assembly 100 in accordance with an aspect of the presentdisclosure. The BFP assembly 100 may be installed in a fluid system,e.g., a water supply for a building. In normal operation, the backflowprevention assembly 100 operates to carry fluid in only a forwarddirection, e.g., left to right in FIGS. 1 and 2 , from an inlet 116 toan outlet 120. The BFP assembly 100 operates to prevent flow in abackward direction, i.e., a direction from right to left in FIGS. 1 and2 .

The BFP assembly 100 includes a body 104 forming an upstream bucket 108and a downstream bucket 112. Each bucket 108, 112 is enclosed by a testcover 118, 122. The test covers 118, 122 may include one or more testcocks 140 for sensing pressure at various locations within the BFPassembly 100. The downstream test cover 118 includes two test cocks 140and the upstream test cover 122 includes a single test cock 140 but thetest covers 118, 122 are otherwise very similar.

Each bucket 108, 112 includes a check valve assembly 150 for selectivelyopening and closing flow through the respective bucket 108, 112.Preferably, the check valve assemblies 150 are interchangeable althoughas shown, the check valve assemblies 150 are different. Each check valveassembly 150 has frame 170 fit into the respective bucket 108, 112. Theframe 170 retains a valve member 200, which selectively closes against acircular valve seat 172 of the frame 170. The valve members 200 aregenerally disc-shaped with an annular sealing region 204 that sealsagainst the valve seat 170. The valve member 200 is connected to theframe 170 by a hinge portion 206 that allows rotation of the valvemember 200 away from the valve seat 172 to open flow.

In each check valve assembly 150, a spring retainer assembly 300provides a biasing force to urge the valve member 200 against the valveseat 172. If the pressure downstream of the valve member 200 exceeds theforce of the spring retainer assembly 300, the check valve assembly 150will open to allow forward flow. If not, the spring retainer assembly300 will keep the check valve assembly 150 closed. The spring retainerassembly 300 extends between the respective test cover 118, 122 and thevalve member 200. The test covers 118, 122 form hollows 124 for couplingto the spring retainer assembly 300 whereas the valve member 200 has aretention cup 210 for coupling to the spring retainer assembly 300.

Referring now to FIGS. 3-10 , various views of the spring retainerassembly 300 are shown. The spring retainer assembly 300 includes atelescoping central portion 302. The telescoping central portion 302includes a somewhat tubular cylinder portion 310 with an open lip end312. The open lip end 312 has internal threads 314 best seen in FIGS. 6and 10 . A closed free end 316 opposes the open lip end 312 and has aspherical or bulbous shape for coupling to the retention cup 210 of thevalve member 200 or in the hollow 124 of the test cover 118, 122, as thecase may be. Adjacent the bulbous closed free end 316, a retentioncollar 318 is formed.

The spring retainer assembly 300 also includes a piston portion 330 thatpartially slides within the cylinder portion 310. The piston portion 330has a tab end 332 that is captured within the cylinder portion 310. Thetab end 332 has outer threads 334. To couple the cylinder portion 310and the piston portion 330 together, the tab end 332 is threaded throughthe open lip end 312 of the cylinder portion 310. Once coupled, the tabend 332 can slide within the cylinder portion 310 but is retained by thelip end 312 until unscrewed.

The piston portion 330 has a free end 336 with a retention collar 338. Aspring 350 is captured and compressed between the retention collars 318,338 to urge the cylinder portion 310 and piston portion 330 apart asbest seen in FIGS. 3-5 . Thus, when in the spring retainer assembly 300is in place between the fixed rigid hollow 124 of a test cover 118, 122and retention cup 210 of the valve element 200, the spring 350 providesthe biasing force to urge the valve element 200 closed (see FIGS. 1 and2 ).

As illustrated in FIGS. 7-10 and shown in the downstream check valveassembly 150 of FIG. 2 , the spring retainer assembly 300 is compressedby opening of the check valve assembly 150 when the upstream pressure onthe valve member 200 exceeds the force provided by the spring 350. Inother words, the force of the spring 350 is predetermined to allow thevalve element 200 to permit the normal flow of fluid in the forwarddirection.

In order to minimize wobbling or lateral motion of the piston portion330 during sliding, an inner diameter D1 of the cylinder portion 310 isapproximately the same as the outer diameter D2 of the threaded tab end332 (see FIG. 6 ). The threaded tab end 332 also has sufficient lengthalong the axis of movement to be stable inside the cylinder portion 310.In this way, the piston portion 330 moves linearly and is prevented fromwobbling. The length of the threaded tab end 332 and cylinder portion310 are selected to minimize wobbling while still allowing sufficienttravel for a fully open and closed check valve 150.

In normal operation, the force exerted by the respective spring retainerassembly 300 on the valve elements 200 is overcome by the pressureexerted by the fluid normally flowing from the inlet 116 to the outlet120 so that both check valves 150 are open. If, for example, there is adrop in pressure from the supply source, the upstream valve element 200and the downstream valve 200 will close to prevent backflow as shown inFIG. 2 . Similarly, if the normal forward flow is interrupted, one orboth of the valve elements 200 is urged in position to cover the valveseat 172 (e.g., FIGS. 1 and 2 , respectively) to close the check valve150 and prevent backflow.

To assemble a check valve 150, the threaded tab end 332 of the pistonportion 330 is screwed through the threaded lip end 312 of the cylinderportion 310 to couple the piston portion 330 to the cylinder portion310. Either end 316, 336 may be coupled to the retention cup 210 of thevalve element 200 because each end 316, 336 is similarly shaped.Preferably, the retention cup 210 is flexible and deforms slightly toreceive the spherical end 316, 336 without requiring any tools. Oncepopped in, the bulbous end 316, 336 easily rotates within the retentioncup 210. As the test cover 118 is mounted is mounted on the check valve150, the other end 316, 336 of the spring retention assembly 300 isaligned to the hollow 124, which captures the end 316, 336 while alsoallowing for easy rotation of the end 316, 336 therein. Thus, the springretention assembly 300 can be arranged in a reverse arrangement to thatwhich is shown and assembly is simplified.

Repair of the spring retention assembly 300 is also simplified. Forexample, if the piston portion 330 is broken, the threaded tab end 332is unthreaded from the cylinder portion 310. To replace the brokenpiston portion 330, a new piston portion 330 can be threaded into thepreviously used cylinder portion 310. Similarly, without tools, theportions 310, 330 can be separated to replace the helical spring 350.

In one embodiment, the ends 316, 318 include a spherical portion 319having a threaded post 321 that screws into or otherwise mounts to theretention collar 318, 338. Hence, the threaded posts 312 are the same sothat fewer parts are required and manufacturing and repair issimplified. Further, as tools are not required, assembly is simplified.In another embodiment, the ends 316, 318 are different sizes to precludereversibility. For example, only one end 316, 318 may be small enough tofit into the retention cup 210 so that there is only one orientationthat couples the spring retention assembly 300 to the valve element 200.

In another embodiment, the spring retention assembly does not include ahelical spring around the outside. Instead, the helical spring or even acompressible insert is provided with the cylinder portion to generatethe proper bias.

Referring now to FIGS. 11A and 11B, isolated side and perspective viewsof a frame 170 for use in a check valve assembly in accordance with thesubject disclosure are shown. The frame 170 snugly fits into therespective bucket. A top portion 174 seals against the BFP assembly bodyand a lower portion 177 narrows the fluid path through the BFP assemblyto an opening 175 of the valve seat 172. The top portion 174 includes acircular ledge 182 that acts as an insertion hardstop. A retaining nut126 (see FIG. 1 ) threads onto the body 104 to secure the frame 170thereto. The valve seat 172 also includes an annular raised rim 176 as asealing surface with a recess 178 surrounding the rim 176.

The frame 170 includes standoff 179 adjacent the opening 175 and forminga pair of opposing notches 180. The notches 180 may be U-shaped toreceive a valve member such that the valve member is hinged to the frame170 for selective opening and closing of the opening 175. The notches180 may also simply be holes or similar shape to receive a protrudingtab to create a hinge arrangement.

Referring now to FIG. 12 , a partial cross-sectional view of areversible valve member 400 coupled to a frame 450 in a check valveassembly of a BFP assembly in accordance with the subject disclosure isshown. Like reference numerals in the “400” series are used to refer tosimilar elements between the frame 170 and the frame 470. Similarly“400” series numbers are also used to describe like elements between thevalve members 200, 400 so that the following description can be directedto the differences.

The valve member 400 is reversible by being symmetrical. The valvemember 400 has a central disc 402. Each side of the central disc 402 hasa central retention cup 410. The cups 410 have a plurality of fingers412 that deflect to allow manual insertion of the end 316 of the springretention assembly 300 to capture the end 316 therein. Once captured,the end 316 can smoothly rotate within the cup 410 like aball-and-socket joint. Similar connections like a condyloid joint,saddle joint, hinge joint, pivot joint and the like may be used. Thevalve member 400 also has a radially outward ring-shaped sealing region404 on each side 408. An outer edge 414 of the central disc 402 may berelatively thicker than the sealing region 404. The hinge portion 406extends from the outer edge 414 of the central disc 402. In oneembodiment, the sealing surface 476 is a ring-shaped elastomeric inserton each side 408.

Once assembled, as shown in the closed position in FIG. 12 , the springretention assembly 300 urges the valve member 400 against the valve seat472. The sealing region 404 of the valve member 400 and the sealingsurface 476 of the frame seat 172 are sealingly engaged to close theopening 475. When the upstream fluid pressure exceeds the urging forceof the spring retention assembly 300, the valve member 400 rotates toopen the opening 475 and, in turn, the end 316 rotates within thedeflectable fingers 412 of the retention cup 410.

By being symmetrical, the valve member 400 can be arranged in a reversearrangement and work in the same manner. Thus, assembly is simplified.Further, repair of the valve member 400 is also simplified. For example,if the valve member 400 is broken on one side in the field, rather thanlocate a replacement part, the valve member 400 can be unhinged, flippedand rehinged. As a result, the required number of parts is reduced withassembly and repair simplified. Preferably, tools are also not required.

Referring now to FIGS. 13A and 13B, isolated views of another reversiblevalve member 500 for use in a check valve assembly in accordance withthe subject disclosure are shown. As will be appreciated by those ofordinary skill in the pertinent art, the valve member 500 utilizessimilar principles to the valve members 200, 400 described above.Accordingly, like reference numerals in the “500” series are used toindicate like elements.

The primary difference of the valve member 500 is the sloped sealingregion 504 as best seen in FIG. 13B. The sloped sealing region 504 maybe formed by partially fully coating the central disc 502.Alternatively, the entire central disc 502 may be formed from anelastomeric or other material with the desired sealing properties. Thevalve member 500 is still symmetrical about an axis of symmetry “a” forreversibility.

The hinge portion 506 includes a pair of opposing radially extendingflexible arms 507. The arms 507 have distal tabs 509 protruding outwardto engage the frame. By manually deflecting the arms 507 inward (e.g,closer together), the tabs 509 can be snap-fit into the notches of theframe. In another embodiment, the hinge portion and the standoff of theframe have transverse passages for receiving a hinge pin to create thehinge. It is envisioned that the tabs 509 may simply rest in the notcheswith the force of the spring assembly being sufficient so that the tabs509 float in place to allow easy freedom of movement.

Referring now to FIG. 14 , an isolated perspective view of thetelescoping spring retention assembly 300 coupled to the reversiblevalve member 500 in accordance with the subject disclosure is shown.Again, if the valve member 500 becomes damaged in the field (e.g., oneof the cups 512 become broken), the valve member 500 can simply beflipped and reinstalled without tools in the check valve assembly.Similarly, the orientation of the valve member 500 and spring retentionassembly during initial assembly is not important, which makes assemblyeasier.

Referring now to FIGS. 15-18 , various views of another spring retainerassembly 600 are shown. Similar elements to those described inconnection with above-described embodiments are indicated with the likereference numbers in the “600” series. Many elements are essentially thesame as those of the foregoing embodiments and, thus, are not furtherdescribed herein. Thus, the following description relates to thedifferences of the spring retainer assembly 600.

The spring retainer assembly 600 has a piston portion 630 with opposingbuttons 611 near the end 632 for coupling to the cylinder portion 610.The cylinder portion 610 forms opposing two-part slots 613 that capturethe buttons 611 to guide the telescoping motion. Each two-part slot 613has a cross-wise portion 615 and an axial portion 617. During normaloperation, the buttons 611 are captured in the axial portion 617 of thetwo-part slots 613 to guide linear motion and prevent the springretainer assembly 600 from coming apart if the test cover is opened orremoved. As shown in FIG. 17 , the spring retainer assembly 600 is fullyextended.

To assembly the spring retainer assembly 600, the piston portion 630 ispressed into the cylinder portion 610. The cylinder portion 610 hasangled internal ramps 623 that guide the buttons 611 into axial grooves625. The axial grooves 625 guide the buttons 611 in the cross-wiseportion 615 of the two-part slot 613 (FIG. 16 ). Once the buttons 611are in the slot 613, the piston portion 630 can be rotated along arrow627 as shown in FIG. 18 to be in the operational position within theaxial portion 617 of the slot 613. In another embodiment, the buttons611 are push-buttons that retract during insertion into the slot 613. Instill another embodiment, the slot 613 extends toward the open end(e.g., along the line of the groove 625). The cylinder portion 610 mayalso be somewhat deformable so that the cylinder portion 610 can beflexed to insert the buttons 611 in the slots.

As can be seen, the subject disclosure provides many improvements to BFPassemblies 100. For example, without limitation, the BFP assemblies 100are more easily manufactured by simplification and/or reversibility ofcomponents. The assembly is not only easier but more error proof due toimproved design of components. Similarly, repair is also faster, easierand less complex. Further, the subject technology can be adapted to anykind of valve.

It will be appreciated by those of ordinary skill in the pertinent artthat the functions of several elements can, in alternative embodiments,be carried out by fewer elements, or a single element. Similarly, insome embodiments, any functional element can perform fewer, ordifferent, operations than those described with respect to theillustrated embodiment. Also, functional elements (e.g., check valves,valve elements, spring retention assemblies, and the like) shown asdistinct for purposes of illustration can be incorporated within otherfunctional elements in a particular implementation.

While the subject technology has been described with respect to variousembodiments, those skilled in the art will readily appreciate thatvarious changes and/or modifications can be made to the subjecttechnology without departing from the scope of the present disclosure.

1. (canceled)
 2. A spring retention assembly for a valve assembly,comprising: an elongated cylinder portion having an open end and aclosed end; an elongated piston portion having a free end and a capturedend configured to be slideably captured in the elongated cylinderportion; and a spring coupled to the cylinder portion and the elongatedpiston portion to provide a force to urge the elongated cylinder portionand the piston away from one another, wherein the closed end and thefree end are similarly shaped so that the spring retention assembly canbe reversibly mounted.
 3. The spring retention assembly of claim 2,wherein the open end and the captured end are threaded so that thecaptured end threads through the open end.
 4. The spring retentionassembly of claim 2, wherein: the elongated cylinder portion has aretention collar; the elongated piston portion has a retention collar;and the spring is helical and extends between the retention collars. 5.The spring retention assembly of claim 2, wherein the spring is under apredetermined amount of compression less than an amount of force of anormal forward flow of fluid in a backflow prevention system.
 6. Thespring retention assembly of claim 2, wherein: an inner diameter of theelongated cylinder portion and an outer diameter of the captured end areapproximately equal so that lateral movement of the elongated pistonportion is reduced.
 7. The spring retention assembly of claim 2, whereinthe spring is within the elongated cylindrical portion.
 8. The springretention assembly of claim 2, wherein the elongated cylinder portionforms at least one axial slot and the elongated piston portion has atleast one button captured in the at least one slot to guide motion ofthe elongated piston portion.
 9. A spring retention assembly for a valveassembly, comprising: a central portion with a first free end and asecond free end, wherein the ends are similarly shaped so that thespring retention assembly can be reversibly mounted.
 10. The springretention assembly of claim 9, wherein a housing of the valve assemblyforms a hollow for receiving either of the ends and a valve elementincludes a retention cup for receiving either of the ends.
 11. Thespring retention assembly of claim 9, wherein the central portion istelescoping and further comprising: a first retention collar on thefirst free end; a second retention collar on the second free end; and aspring extending between the retention collars to urge the telescopingcentral portion to elongate.
 12. The spring retention assembly of claim11, wherein the ends are configured to mount to either retention collar.13. The spring retention assembly of claim 9, wherein the ends arebulbous. 14-19. (canceled)
 20. A spring retention assembly comprising: acylinder portion including: an open threaded end; a closed end; and afirst retention collar adjacent the closed end; a piston portionincluding: a threaded tab end configured to thread through the openthreaded end and, thereby, be captured in the cylinder portion forsliding motion; a second end; and a second retention collar adjacent thesecond end; a spring extending between first retention collar of thecylinder portion and the second retention collar of the piston portionto provide a force to urge the piston portion Out of the piston portion,wherein the spring provides a predetermined amount of extending forceless than a flow force of fluid in a back low prevention system.
 21. Thespring retention assembly of claim 20, wherein an inner diameter of thecylinder portion and an outer diameter of the threaded tab end areapproximately equal so that the threaded tab acts as a stabilizing guideduring the sliding motion.